editors, Dermot Englefield, Gavin Drewry
Butterworth, 1984
Buku Referensi
Prytherch, Ray
Gower, 1987
Buku Referensi
Parker, Christopher Charles
Butterworths, 1960
Buku Teks SO
edited by C.P. Ager
Bowker-Saur, 1992
Buku Referensi
editors, L.T. Morton, S. Godbolt
Butterworth, 1984
Buku Referensi